1. Field of the Invention
Implementations of various technologies described herein are directed to volatile organic compound (VOC) detection and to various methods and/or systems for igniting a flame in a volatile organic compound (VOC) detector, e.g., reigniting a flame that has been extinguished in a volatile organic compound (VOC) detector.
2. Description of the Related Art
The following descriptions and examples do not constitute an admission as prior art by virtue of their inclusion within this section.
Industrial plants that handle volatile organic compounds (VOCs) sometimes experience unwanted emissions of those compounds into the atmosphere from point sources, such as smokestacks, and non-point sources, such as valves, pumps, and/or vessels containing the VOCs. Emissions from non-point sources typically occur due to leakage of the VOCs from joints and/or seals and may be referred to herein as “fugitive emissions”. Fugitive emissions from control valves typically occur as leakage through the packing set around the valve stem. Control valves used in demanding service conditions involving large temperature fluctuations and frequent movements of the valve stem commonly suffer accelerated deterioration of the valve stem packing set.
The United States Environmental Protection Agency (EPA) has promulgated regulations specifying maximum permitted leakage of certain hazardous air pollutants, such as benzene, toluene, 1,1,1-trichloroethane, from certain hardware or fixtures, e.g., control valves. The regulations require facility operators to perform periodic surveys of the emissions from all control valves and pump seals. The survey interval frequency may be monthly, quarterly, semiannual, or annual. If the facility operator can document that a certain percentage of valves and pumps with excessive leakage are below a prescribed minimum, the required surveys become less frequent. Thus, achieving a low percentage of leaking valves reduces the number of surveys required per year, which may result in large cost savings.
Fugitive emissions are typically monitored using a VOC detector, which may also be referred to as a vapor analyzer. Due to the location of the control valves and a tendency to jar the VOC detector during operation, the flame inside the VOC detector may often go out during detection. When this happens, the technician operating the VOC detector may need to reignite the flame, e.g., by manually reigniting the flame. Manual reignition has a number of disadvantages, including having to unstrap the VOC detector from the back of the technician. If the flame extinguishes while the technician is in the process of climbing up a ladder on a structure, e.g., en route to a location where detection will take place, then the entire detection process is disrupted and often, for safety reasons, the technician not only has to stop climbing the ladder, but changes direction and goes back down the ladder, so that the VOC detector can be safely unstrapped and the flame manually reignited. Accordingly, there is an ongoing need for the methods and systems disclosed below.